Nope. I am talking about both private and public schools. Go to any top tier school districts and you’re going to find these students. Just want to be clear that I am not criticizing these students. I am criticizing the OP narrative that US students are bad at math and sciences. We have the best schools period. Not even close. We churn out the best talent. Again not even close.
The US is a large place, and the fact that great highschools exist doesn't tell us anything about the distribution of highschool quality, except for that one fact.
Private schools are not the norm though, and public schools like that are even rarer.
I agree that America's education system has higher variance.